The invention relates to speech coding, such as for computerized speech recognition. Speech coding involves the generation of an electrical signal representing at least some information about an utterance.
Speech coding devices and speech recognition systems may be either speaker-independent, or speaker-dependent. Speaker-independent speech recognition systems have parameters whose values are fixed for all speakers who use the system. Speaker-dependent speech recognition systems have at least some parameters whose values for one speaker differ from the parameter values for other speakers.
By choosing suitable parameter values for each individual speaker, the speaker-dependent speech recognition system generally achieves a higher word recognition rate (or a lower word error rate) than a speaker-independent speech recognition system. However, a relatively large amount of training data is required from each new speaker in order to obtain speaker-dependent parameter values which will yield a suitably high word recognition rate.